The meter test
Turn off every faucet, appliance and the irrigation system. Look at the water meter's leak indicator (usually a small triangle or dial). If it keeps moving, water is escaping somewhere. Close the main shutoff: if the indicator stops, the leak is inside the house, which on a slab home often means under the floor.
Warning signs on a slab foundation
- A warm or hot spot on tile or wood (a hot-water line leak)
- Sound of running water with everything off
- Damp carpet, cupping hardwood or mildew at the base of walls
- Low water pressure throughout the house
- Cracks in flooring or new foundation cracks
How plumbers find it
Plumbers isolate the hot and cold lines with pressure tests, then pinpoint the leak with acoustic listening equipment and thermal imaging so any opening is as small as possible. See leak detection.
Repair options
A spot repair through the slab fixes one leak. When pipe under the slab is old or has leaked before, rerouting the line through walls or the attic often costs less over time than repeated slab repairs. See slab leak repair.
Insurance
Many policies cover the resulting water damage and sometimes the cost to access the pipe, but not the pipe repair itself. Photograph damage and call your insurer early.
Signs of a Slab Leak (and What to Do Next): when to call a pro
- A warm spot on a tile or concrete floor
- Water meter moves with everything off
- Sound of running water with no fixtures on
- Damp carpet or cupped wood flooring
Signs of a Slab Leak (and What to Do Next): common questions
Are slab leaks common in Charlotte?
They happen on slab homes of any age, most often where copper lines run under the slab in contact with concrete or soil, and in homes with high water pressure.
Is a slab leak an emergency?
An active leak should be dealt with within days: it wastes water, can damage flooring and may undermine soil under the slab. Shut off the main if the leak is large.
Every home differs; editorial standards.